With three unspectacular options to replace Ben Roethlisberger, many assumed the Pittsburgh Steelers would be hoping to simply survive their star quarterback's four-game suspension.

The return of their once-vaunted defense has them thriving.

Seven forced turnovers made Charlie Batch's reserve role much easier last week, and the veteran would love a similar boost Sunday when he leads the visiting Steelers against the Tampa Bay Buccaneers in a battle of unlikely unbeatens.

Pittsburgh (2-0) hasn't scored an offensive touchdown in regulation - Rashard Mendenhall's 50-yard overtime burst in Week 1 against Atlanta is its only visit to the end zone - but its defense has kept the pressure off an offense missing its two-time Super Bowl-winning signal-caller.

It was the Steelers' defense that struggled without safety Troy Polamalu and lineman Aaron Smith during a five-game skid last season, but one of the NFL's most physical units appears to be back. Pittsburgh shut down rushing champ Chris Johnson last Sunday in a 19-11 win at Tennessee in which the offense finished with 21 passing yards.

"We've got a chip on our shoulder this year because of how things went down last year with our losing streak," nose tackle Chris Hoke said. "So we have something to prove. Sometimes when people wrote that we're not going to be very good or maybe they'll go 2-2 or 1-3 when Ben's out, that's a lot of the stuff that (makes us mad)."

The Steelers won't be any worse than 2-2 when Roethlisberger returns, but they haven't had much luck keeping any of his replacements healthy.

Dennis Dixon was lost in the first half at Tennessee with a torn meniscus, leaving Batch - the only remaining QB on the roster - to play the rest of the way.

Now apparently healthy again is Byron Leftwich, who suffered a knee injury in the final preseason game and was actually released prior to Sunday's game to allow the team to dress an additional defensive lineman. The Steelers re-signed him Monday.

But after speculation that Leftwich - who started three games for Tampa Bay in 2009 - would start, coach Mike Tomlin announced Wednesday that Batch will get the call.

Leftwich's return to Tampa won't be Sunday's only significant reunion. Tomlin was the Bucs' defensive backs coach from 2001-2005 before becoming Minnesota's defensive coordinator, and in 2007, the NFL's youngest head coach in Pittsburgh.

That's a title that now belongs to Tampa Bay's Raheem Morris, who worked as an assistant with Tomlin before being hired last season.

"We always used to talk about competing against each other," Morris said. "We have the opportunity to go out there and compete on a top stage and there's nothing better than that. ...

"We might have a phone call or two (this week), but it's safe to say we won't be exchanging information."

Tomlin isn't the only defensive-minded coach that has to like the look of his club. The Steelers are tied for first in the NFL in allowing 10.0 points per game, and Tampa Bay is giving up an average of 10.5.

The Bucs (2-0) have forced three turnovers in each game, and after a 20-7 win at Carolina in Week 2, Morris' team might be the NFL's most surprising unbeaten.

"They're playing with a little bit of wisdom beyond their years," Morris said. "We've been winning as a team ... with everybody contributing. That's the only way we can do it."

Josh Freeman has led the way. The second-year quarterback has thrown four touchdowns and one interception, a far cry from the 13 picks he threw in his final five games of 2009 after supplanting Leftwich as the starter.

"You go out there and he tells you to calm down and bring your route and he has you," rookie receiver Mike Williams said. "You here that from a quarterback and you're like, 'Dang, all I have to do is just catch the ball.'"

Freeman will likely have to attack the Steelers through the air. Atlanta's Michael Turner and Tennessee's Johnson - All-Pros over the past two seasons - combined for 35 carries and 76 yards rushing against Pittsburgh, which should get nose tackle Casey Hampton (hamstring) back Sunday.

The Steelers will probably stick to Mendenhall and the ground game with Batch starting for the first time since 2007. They'll likely have left tackle Max Starks (ankle) back as they seek their second 3-0 start since 1993.

Tampa Bay, though, will be without safety Tanard Jackson, who was suspended for a minimum of a year without pay Wednesday for violating the NFL's substance abuse policy.

Jackson sat out the first four games of 2009 while serving a previous suspension for violating the substance abuse policy. He finished with five interceptions in 12 starts and had 13 tackles in two games this season.

Pittsburgh is 7-1 against Tampa Bay, which hasn't started 3-0 since 2005.